I am simple sharing this.
The Author/Creator of this cheat is BigBossTS/FallDownTheSystem
This is a neat program that suggest best moves for chess(dot)com/Lichess/Chess24 and recent one is ArenaMyFide sites.
A userscript, which can read the moves from the said chess website below, send them to a python backend through a websocket.
The python script connects to an UCI engine, such as stockfish, calculates best moves either through analysis, opening books or end game tables and reports back to the userscript.
The cheat is capable of showing multiple principal variations (lines of play), reading the best move out loud through text to speech, and drawing the best move and response over the board on an overlay.